Is this a homework problem or something you made up? When I set up the Riemann sum I ended up with an expression involving the sum of the square roots of the first n positive integers. There is a complicated formula for that involving Bernoulli numbers. So this is a hard problem unless there's some trick I didn't see.

Is this a homework problem or something you made up? When I set up the Riemann sum I ended up with an expression involving the sum of the square roots of the first n positive integers. There is a complicated formula for that involving Bernoulli numbers. So this is a hard problem unless there's some trick I didn't see.

exactly, when you use a fractionation regular you will get a complicated formula. However, if you use not a regular fractionation as , you can deal with this.